This section introduces aspects that may be helpful in facilitating a better understanding of the invention. Accordingly, the statements of this section are to be read in this light and are not to be understood as admissions about what is in the prior art or what is not in the prior art.
Several technical terms and/or phrases will be used throughout this application and merit a brief explanation.
The 3rd Generation Partnership Project (3GPP) attempts to create a uniform third-generation mobile phone system. 3GPP standards are called releases and different functionality is present in the different versions of the releases.
The 3GPP standards continue to evolve and the major releases of the standards can be differentiated using supported features. However, there also may be differences between minor versions of the 3GPP standards that render them incompatible with each other. It is required that a single release of the Policy and Charging Rules Function (PCRF) be used with different networks operating with different minor versions of the standards.
A base transceiver station (BTS or BS) is used between a mobile phone and a network to permit wireless communication. It can be a radio base station (RBS), node B for 3G networks or enhanced node B for long term evolution (LTE) networks.
A global system for mobile communications (GSM) network includes a network and switching subsystem (NSS) with a mobile switching center (MSC) and associated registers (e.g. home location register (HLR) and visitor location register (VLR)), a base station controller (BSC) and multiple BTSs and an operations support system (OSS).
The GSM originally only involved a circuit switched network for voice calls and short messaging services (SMS). However, it was extended to include packet-switched data services via the General Packet Radio Service (GPRS) core network to permit Internet access.
A MSC is the service delivery node for GSM in charge of routing voice calls. The gateway MSC (GMSC) is an MSC that ascertains the location of a subscriber who is being called by checking the HLR. The gateway MSC also interfaces with the Public Switched Telephone Network (PSTN).
The HER is a central database containing mobile phone subscriber information. A VLR is a temporary database containing information related to mobile phone subscribers that are roaming in an area the VLR serves. Each BTS is served by a VLR.
A gateway GPRS Support Node (GGSN) permits interaction between the GPRS network which is used for transmitting Internet Protocol (IP) packets and external packet switched networks. When a GGSN receives data addressed to a user, it is forwarded to the serving GPRS support node (SGSN) for delivery to the mobile stations in its service area.
System architecture evolution (SAE) is the architecture of 3GPP's LTE wireless communication standard. The evolved packet core (EPC) is the equivalent of GPRS networks and includes a mobile management entity (MME), a serving gateway (SGW), a Public Data Network (PDN) gateway (POW or PDN GW), and a policy and charging rules function (PCRF) node.
The MME is the control node for the LTE network. It tracks mobile devices and selects the SGW for a mobile device. The SGW sends data packets while the PGW permits the mobile phone to connect to external data networks. The PCRF node is a concatenation of Policy Decision Function (PDF) and Charging Rules Function (CRF).
Currently, all components in a network implement the same or compatible minor versions of the 3GPP standards. New product releases are required to implement the supported 3GPP standards version of the network. However, it is not always possible during trials of product releases (i.e. live deployments) to change product releases. It is also a maintenance issue to have multiple versions of a product for the multiple minor versions of the 3GPP standards. There is no means to distinguish between minor versions of the 3GPP standards and/or determine which minor version is being used in a network component.
Hence, there is a need for a device that efficiently, reliably and affordably permits operation in a mode compatible with different versions of the 3GPP standards and a methodology that permits determination and selection of different versions of the 3GPP standards at the PCRF node.